The present invention relates generally to clothes dryers and in particular to methods and apparatus for treating the exhaust air of a clothes dryer.
Clothes dryers are known which are of the non-venting type, i.e., they contain a built-in dehumidifying mechanism for condensing the moisture from the moist exhaust air. That dried exhaust air is then conducted back into the dryer (e.g. see Lanciaux U.S. Pat. No. 4,621,438). Such a non-venting dryer can be used in dwellings which do not permit venting of utilities such as dryers. The dehumidifying mechanism may utilize a conventional refrigeration cycle wherein a compressor delivers refrigerant sequentially to a condenser section, an expansion valve, and an evaporator section. The dryer exhaust air is directed sequentially across the evaporator and condenser sections and then back to the dryer. In the evaporation section moisture in the exhaust air is condensed out and collected. In the condenser section, heat is returned to the dry air received from the evaporator section.
One shortcoming of known non-venting clothes dryers having a built-in dehumidifying mechanism is that they are expensive. Also, people already possessing a venting dryer who move into a dwelling where venting is prohibited find that their existing dryer is useless and must purchase an expensive non-venting dryer.
Furthermore, a non-venting dryer is heavier and mechanically more complex than a venting dryer, thereby being more susceptible to mechanical breakdown. If the humidifying mechanism suffers a breakdown, it cannot be conveniently taken to a repair shop due to the large size and weight of the dryer; rather, a repairman must come to the dryer.
Therefore, it would be desirable to enable the above discussed shortcomings to be alleviated.